The requirement for a rotatable double-ended quick connect valve arose with the development of a new mould transfer mechanism described in U.S. Pat. No. 5,174,863 awarded to Emery in December of 1992. In the operation of this mould transfer system, vented dies containing wet moulded pulp preforms are mounted in groups on a series of rotatable shaft assemblies transferable from one rotor to another and transported on a series of transfer rotors between the forming rotor and the hot press drying rotor, and it is necessary to maintain a continuing vacuum supply to each die in order to hold the wet preforms in place as they travel about on the transfer rotors and are transferred from one rotor to another.
In the operation of the embodiment shown in the drawings, each of the transporting rotors has a multiplicity of support positions, each to receive, one at a time, and then released to another rotor, a continuing series of said rotatable and transferable shaft assemblies, each of said shaft assemblies being fitted with a rotatable double-ended quick connect valve serving the vented dies and each of said support positions being fitted with a single ended quick connect valve rigidly fixed in a position to mate with a quick connect valve function at one end of said rotatable double-ended quick connect valve mounted on said shall assembly. When said shaft assembly is being transferred from a support position on one of said rotors to a support position on the next following rotor, the two quick connect valve functions, one at each end of said double-ended quick connect valve, are then connected and mated simultaneously with each of the two related single ended quick connect valves, mounted one on each of the two support positions, one on each rotor, on which said shaft assembly is simultaneously supported at the instant of beginning the transfer from one of said rotors to the next following rotor.
Because the supply of vacuum to the vented dies on each shaft assembly is directed from a fixed valve position on the transporting rotor to a fixed pipe connection on the shaft assembly on which said vented dies are transported, and because in some arrangements and on some rotors it is necessary for said shaft assembly to rotate through an angle of rotation of 300 degrees or more on one of said rotors, it is prohibitively difficult to use a hose connection between the rotor source and the rotating die positions, and therefore, it is necessary to arrange for the double-ended quick connect valve to be rotatable on the shaft in relation to the pipe connection to said shaft assembly.